QGIS

QGIS Open Day Brasil Setembro/2021 - Como elaborar mapas para publicações internacionais usando o QGIS

Presentation at QGIS Open Day Brasil Setembro/2021

Trick to fix broken polygon geometries in QGIS 3.X

First, I will create a purposefully invalid geometry to apply the fix. Then, I will show you two ways to fix it. In one of them, I simply apply the “Fix geometries” native tool of QGIS. The second option I will show here is using the buffer tool. In this simple trick, I will show you how to create an infinitesimal buffer around my broken geometry, which ends up fixing it, but has its perks as well.

How to use QGIS 3.20+ to generate outstanding river and drainage net map representations

The first thing I thought when I saw the “Interpolated Line” symbology (I described this functionality in another post) was that it would be useful to represent drainage networks. Today, that is what we are exploring. Innovative ways to represent your river network to depict the watershed in an even more elegant and informative way, using the “Interpolated Line” functionality.

How to create custom geometries based on vector shapes to use on the map legend or symbology on QGIS

This week, I am showing you how to create custom geometries to enhance your legends on QGIS Print Layout. Specifically, how to create these geometries based on vector files that you already have. The example I will provide is how to create the Legend Patch Shape for the state of Rio Grande do Sul, in Brazil.

How to read grib2 raster data on Python

I use pygrib to open the files. In their documentation, they point to two ways to install pygrib, using pip or using conda. However, I could only make it work using conda. Run this in your Anaconda Prompt to install pygrib.

A draggable Truesize Leaflet map of the Brazilian states, and how to do the same for your own country or region

The good news is that using Leaflet Truesize plugin, you can add your own customized draggable polygons to the map. A map that I thought almost immediately is the representation of the draggable Brazilian states, so you could compare them to each other and to the size of other countries. And that is why this is used as an example for this tutorial.

How to generate a Leaflet.js webmap on QGIS with qgis2web plugin, and how to adjust some fundamental features on the map directly on html and JavaScript

Leaflet maps can definitely be generated from scratch. Many people and companies do that. But, because I am a QGIS enthusiast and many of my maps are already on QGIS projects, I can get the best of both worlds. I generate my basic map using as many specifications available on qgis2web as possible, and then, edit the html and the JavaScript generated by the plugin to adjust the map to my needs.

Workaround for: qgis2web freezes while changing map type

So far, so good, but then you try to change the type of map between the available options (currently, OpenLayers, Leaflet and Mapbox GL JS) QGIS freezes and you have to close the application via Windows Task Manager. I observed the occurrence on QGIS 3.20 Odense and on QGIS 3.16 Hannover, version of qgis2web 3.16.

Testing some of my favorite changes in QGIS 3.20 Odense

Today QGIS 3.20 “Odense” was released! In today’s post, I will test some of my favorite features of the new version. To check all the new features and the bugs fixed, check the full Changelog of QGIS 3.20.

Using SAGA Raster Calculator on QGIS - a quick tutorial

The SAGA Raster calculator is useful because it allows to make some calculations that the regular QGIS Raster Calculator does not. Especially, it allows us to use the X and Y coordinates of the raster as inputs for our calculations. How do we start?